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Electric Stunt => Gettin all AMP'ed up! => Topic started by: Ara Dedekian on October 18, 2021, 05:53:02 AM

Title: What's wrong with this battery?
Post by: Ara Dedekian on October 18, 2021, 05:53:02 AM

      This battery is lifeless! It doesn't light up the battery tester, the charger asks, 'where's the battery?!' when it's plugged in and there's no apparent damage or puffyness other than some bunged up insulation. It's a scavenged battery so its history is unknown. It was hoped to use it in a club members e-Twister.

     I'm new to electric systems (RC). What causes a LiPo battery to be so lifeless? I thought I'd find broken wiring and took it apart to run continuity tests. Everything checked out as OK.

     Ara

     
Title: Re: What's wrong with this battery?
Post by: Ara Dedekian on October 18, 2021, 08:29:32 AM


      Motorman

         Thanks so much! Watched the video, I'll try boosting the voltage tonight and let you know the results..

      Ara
Title: Re: What's wrong with this battery?
Post by: Fred Underwood on October 18, 2021, 11:53:22 AM
The video gives specific conditions to be met and that is difficult to know on an unknown battery.

Look at the balance plug and notice the brown area, likely overheated or shorted.  Was the top already messed with, or was that you?

Use a volt meter across the plug and check each cell voltage.  If I understand the video correctly, then the cells should be even and lower than a lipo charger will recognize, at least in lipo mode.

Don't be eager to hook it up to a charge unless you are convinced that it meets the video criteria.  Even if it does meet criteria, don't be eager to hook up a battery with an open top.
Title: Re: What's wrong with this battery?
Post by: Tim Wescott on October 18, 2021, 12:13:43 PM
And if you're going to play with it, do it outside.  LiPo batteries like to burst into flame, and since they have fuel and oxidizer in one handy package, there's no putting them out -- you just wait them out.
Title: Re: What's wrong with this battery?
Post by: William DeMauro on October 18, 2021, 03:35:41 PM
Even if you got it to charge, It probably wont have the punch it needs to fly your plane. It is not worth your time or risk. I would never try to revive a lipo. It is like playing with a live hand grenade as far as I am concerned. New ones are not that expensive. Just my 2 cents.
Title: Re: What's wrong with this battery?
Post by: Ara Dedekian on October 18, 2021, 03:37:12 PM
     
      Fred

         I forgot to mention that besides the RC battery checker, my multimeter didn't find any voltage. I stripped the battery to do a continuity test, which came out OK. This is an exercise on learning about LiPos. I've got the 35 bucks for a new one. The balance plug in the photo is also a mystery. There's nothing burned or damaged near the stain.

      Tim

         I STORE my LiPos outside away from the house. I found some swollen 3 cell RC LiPos and had to see for myself. I set one off in a covered 30 gallon metal barrel and YIKES!! It put the fear of LiPos in me. I knew there was no hope in putting it out. Like Ty says, the smoke was the scariest part.


        So I'll very carefully, outdoors, go ahead with the voltage boost and report back.

       Ara
Title: Re: What's wrong with this battery?
Post by: Ken Culbertson on October 18, 2021, 04:53:37 PM
Flew my E-Twister on these using a Cobra 2820/12.  I had a set of 4 in rotation and each had over 50 cycles on it with no swelling or loss of power.  Is that price worth trying to save something as dangerous as a wounded Lipo battery?  Bury it with honors and get new ones.

https://www.amazon.com/Zippy-Compact-2200mAh-14-8V-Battery/dp/B07ZRZT5YN/ref=sr_1_3?dchild=1&keywords=lipo+4s+2200+25c&qid=1634598039&s=toys-and-games&sr=1-3
Ken